Dust, which is produced in large quantities as a result of handling, transporting and storage of particulate compositions, especially free flowing powders, is a constant source of annoyance and danger. It is irritating to the eyes and mucous membrane, especially the nasal passages. Constant exposure to dust may cause pulmonary disease either because of local tissue lacerations or because the dust particles serve as carriers for toxic microbes. Certain types of dust, particularly coal dust, form explosive mixtures when they attain critical concentrations.
Dust formation is a special annoyance in the field of hair treatment compositions such as those employed in hair dyeing and hair bleaching or frosting, or as a preliminary step to hair dyeing. Such compositions are well known. They normally contain powdered, oxidizing or bleaching compounds including peroxygenated salts such as perborates, percarbonates and persulfates. These include, for example, ammonium, alkali metal and alkaline earth metal peroxygenated salts. Often the particulate compositions will contain pH controlling agents such as silicates, phosphates and carbonates including, for example, sodium silicate. The presently preferred bleaching agents are persulfates and; of these, ammonium, potassium and sodium persulfate are most preferred. Often, the oxidizing powder will contain mixtures of persulfates such as ammonium, sodium and potassium persulfates. Other ingredients which may be utilized include thickeners, surfactants and the like. A swelling agent such as carboxymethyl cellulose or a vegetable gum is often added to give an emollient property to the final product.
For convenience, the hair treating compositions are provided as dry, free flowing powders which may contain a hydrogen peroxide precursor and are taken up in aqueous media just prior to use. If there is no precursor, the aqueous media will contain hydrogen peroxide. While such compositions are convenient, they do manifest a number of difficulties.
One such difficulty is dust formation caused by collision and abrasion of powder particles with each other during handling, storage and transportation. Another, is that, if the particles are not of uniform size, the finer particles, those most likely to produce dust, are at the top of the package.
Hair treatment compositions are usually provided as fine grained powders containing a number of discrete, dust forming particles of various ingredients with particle sizes below about 40 microns together with larger particles, even as high as 1000 microns. It is the particles of a size up to about 40 microns which are especially troublesome dust farmers. Often, there is a lack of uniformity in the compositions attributed, at least in part, to the fact that the various particles forming them have different apparent densities which causes them to separate during transportation and storage. As a result, the heavier particles concentrate at the bottom of the package while the lighter particles migrate to the top. This lack of uniformity causes variations in the hair treatment results which can be achieved because the portions withdrawn from the package for use are not of uniform composition. One way of alleviating the problem is by appropriate mixing, but this is inconvenient, time consuming and often overlooked. Another possibility is to prepare the compositions with particles of uniform small size, but dust forms every easily from fine particles.
There are many examples of adding various types of liquids or hydrophilic materials to powders to prevent dust formation. In extreme cases, sufficient amounts of such materials are added so that the powders are actually converted to pastes or creams. Generally speaking, these procedures have not been satisfactory because the additions tend to diminish the desirable free flowing characteristics of the powders and, in the case of creams and pastes, totally destroy these properties. Or, if insufficient additive is employed, the composition remains free flowing but still forms appreciable amounts of dust.
Hydrophilic materials, although recommended for producing dust free compositions, are not particularly recommended for hair treatment compositions because the components of such compositions react rapidly with water. Two problems arise with hair bleaches. These are:
1. Ammonium salts and alkali (generally, ammonium persulfate and sodium metasilicate) generate ammonia which is necessary for hair bleaching and will be lost by reacting with water. Further, sodium metasilicate after reacting with the ammonium salt will solidify, being converted to silica, and cannot be redissolved.
2. Persulfates decompose when moist or when heated excessively but the decomposition is more rapid when a moist persulfate is heated. Therefore, the bleaching ability is decreased if it remains wet. It is also decreased if an attempt is made to dry by heating.
For convenience, this invention will be described principally as it relates to hair bleaching compositions, although the terms "hair treating or treatment compositions" should be understood to include both dyes and bleaches. However, it is not limited to hair treating compositions. It may, for example, be employed with alkali metal and ammonium persulfates which are utilized not only in hair bleaching compositions but also in the paint and in the polymer industries.
Typical hair dying compositions which may be treated in accordance with this invention include oxidative, including auto-oxidative, dyes which may be provided as powdered primary intermediates and couplers. Many such products are known. Those which are presently employed on a wide scale include those listed in Table 1, below.
TABLE 1 ______________________________________ Primary p-phenylenediamine Intermediates: p-aminophenol o-aminophenol N,N-bis(2-hydroxyethyl)p-phenylendiamine 2,5-diaminopyridine p-toluene diamine Couplers: resorcinol m-aminophenol 1-naphthol 5-amino-o-cresol 2-methylresorcinal 4,6-di(hydroxyethoxy)-meta-phenylenediamine meta-phenylenediamine Auto-oxidative dyes 2,4-diaminophenol benzene-1,2,4-triol toluene-2,4,5-triol ______________________________________
Semipermanent dyes such as those listed in Table 2 are also included within the ambit of the invention.
TABLE 2 ______________________________________ N-(2-Hydroxyethyl)-o-nitroaniline 4-Nitro-o-phenylenediamin N.sup.1 -(2-Hydroxyethyl)-4-nitro-o-phenylenediamine N.sup.1 -Tris(hydroxymethyl)methyl-4-nitro-o-phenylenadiamine 2-Amino-3-nitrophenol 2-Amino-4-nitrophenol 4-Amino-2-nitrophenol 2-Amino-5-nitrophenol O,N-Bis(2-hydroxyethyl)-2-amino-5-nitrophenol N-(2-Hydroxyethyl)-2-amino-5-nitroanisole 4-Amino-3-nitrophenol N-(2-Hydroxyethyl)-4-amino-3-nitrophenol N-(2-Hydroxyethyl)-4-amino-3-nitroanisole 1-(3-Methylamino-4-nitrophenoxy)propane-2,3-diol 3-Methylamino-4-nitrophenoxyethanol 2-Nitro-p-phenylenediamine N1-(2-Hydroxyethyl)-2-nitro-p-phenylenediamine N4-(2-Hydroxyethyl)-2-nitro-p-phenylenediamine N1-Methyl-2-nitro-p-phenylenediamine N1,N4,N4-Tris(2-hydroxyethyl)-2-nitro-p-phenylenediamine N4-(2-Hydroxyethyl)-N1,N4-dimethyl-2-nitro-p-phenylenediamine N4-(2,3-Dihydroxypropyl)-N,N4-dimethyl-2-nitro-p-phenylenediamine 4-Nitro-m-phenylenediamine Picramic Acid N-Methyl-iso-picramic acid 4-Amino-2-nitrodiphenylamine 4-Hydroxy-2'-nitrodiphenylamine 4-(p-Aminophenylazo)-N,N-bis(2-hydroxyethyl)aniline 1,4,5,8-Tetraminoanthraquinone 1,4-Diaminoanthraquinone 1-Amino-4-methylaminoanthraquinone 1-(2-Hydroxethylamino)-4-methylaminoanthraquinone 2,4-Diamino-2'-hydroxy-5'-nitroazobenzene-5'-sulphonic acid (Sodium salt) ______________________________________
The various liquids and other materials which have heretofor been employed as dust inhibitors in hair bleaching powders have been specific in their usages and have not taken into account the aesthetics of the final product or the compatibility of the deducting agent with the bleach components, or with the hair.
According to German Published Application Number DE 40 26 235 A1, dust free compositions are provided by mixing ammonium, potassium and sodium persulfate granulates having a particle diameter of 0.1 to 0.6 cm with a water soluble thickener, a wetting agent and/or an emulsifier.
U.S. Pat. Nos. 3,838,064; 3,838,092; 3,947,089 and 3,993,584 all relate to the use of special grades of polytetrafluoroethylene (Teflon) to control dust generated by fine powders. This procedure is not completely satisfactory because it is expensive and requires special mixing equipment. Additionally, when used in hair bleaches the small pieces of Teflon become trapped or entangled in the hair similar to gum.
U.S. Pat. No. 3,726,967 describes the use of water soluble polyvinylpyrrolidone or glucose in homogeneous hair bleaching compositions. These additives are solids, require specialized equipment for coating the particles and are not described as reducing dust formation.
U.S. Pat. No. 4,170,637 and German Patent Number DE 3 814 356 C both describe the formation of hair bleaching paste compositions with an anhydrous organic carrier. Such compositions lack the convenience of free flowing powders, are much more difficult to manufacture and, because measurement is difficult, they must be packaged for individual use and are, therefore, not convenient or cost efficient for salon use.